Distributions and seasonal abundances of krill eggs and larvae in the sub-Arctic Godthåbsfjord, SW Greenland

The larval krill community (Thysanoessa spp.) was investigated along the sub-Arctic Godthåbsfjord, SW Greenland, in June 2010. In addition, the progress of krill development from egg to furcilia was studied from March to August 2010 in a fjord branching off the Godthåbsfjord. Krill spawned from late April until early May, with a second spawning event in early July.

Spawning took place in the warmer, innermost part of the fjord, correlated with phytoplankton blooms. Naupliar abundance peaked immediately after spawning, and naupliar stage duration was 3 d. Sequences of the calyptopis and furcilia stages lasted 22 and 63 d, respectively. The growth rate from metanauplius to calyptopis was 0.12 d−1, while the growth rate across all developmental stages was 0.05 d−1.

Mortality rates were calculated as 25% from eggs to nauplii, 48% from eggs to calyptopes and 83% from eggs to furcilia. During development, the larvae were dispersed from the shallow, warmer hatching area in the inner part of the fjord to the main fjord by tidal currents and runoff from land. The study showed that developmental stages of krill are a key group in Greenland coastal waters, one which should be considered in future studies of the pelagic food web